/////////////////////////////////////////////////////////////////////////////////////////////////
//
//  Tencent is pleased to support the open source community by making libpag available.
//
//  Copyright (C) 2021 Tencent. All rights reserved.
//
//  Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
//  except in compliance with the License. You may obtain a copy of the License at
//
//      http://www.apache.org/licenses/LICENSE-2.0
//
//  unless required by applicable law or agreed to in writing, software distributed under the
//  license is distributed on an "as is" basis, without warranties or conditions of any kind,
//  either express or implied. see the license for the specific language governing permissions
//  and limitations under the license.
//
/////////////////////////////////////////////////////////////////////////////////////////////////

#include "UniqueID.h"

namespace pag {
static constexpr uint32_t InvalidUniqueID = 0;

uint32_t UniqueID::Next() {
  static std::atomic<uint32_t> nextID{1};
  uint32_t id;
  do {
    id = nextID.fetch_add(1, std::memory_order_relaxed);
  } while (id == InvalidUniqueID);
  return id;
}
}  // namespace pag